How can we help?
You can also find more resources in our
Select a category
Something is confusing
Something is broken
I have a suggestion
What is your email?
What is 1 + 3?
Concerns body structures seen without the use of microscope.
The study of the cells, tissues, and organs as observed with a microscope.
The development of the individual from the fertilized egg to the adult form.
The study of the cells and how they function.
Study of nerve function.
The excretory system and it's functions.
The study of reproductive organs and the methods for reproduction.
The ultramicroscopic building blocks of matter.
The combination of atoms combining together.
The functional unit of living things.
Group of cells of similar structure working together and performing the same function.
Composed of two or more different kinds of tissues.
Composed of several organs with complementary functions.
The systems operating together, highest level of organization.
Skin, Primary tissue that covers the body surfaces, lines its internal cavities, and forms glands.
Blood and bone Tissue
Four types of tissue:
Epithelial, Connective, Muscle, and Nerve.
Covers the body and protects it. (Skin, hair, nails, and sweat glands)
Protects the body and provides support for the locomotion and movement. (Bones, cartilage, and ligaments)
Receives stimuli, integrates information, and coordinates the body functions. (Brain, spinal cord, nerves, and sense organs)
Chemically coordinates & integrates the activities of the body. (Pituitary, adrenal, thyroid and other ductless glands)
Permits body movement. (Skeletal muscle, smooth muscle, and cardiac muscle.)
Digest Foods and absorbs soluble nutrients from ingested food. (teeth, salivary glands, esophagus, stomach, intestines, liver, and pancreas)
Collects oxygen and exchanges it for carbon dioxide. (Lungs, pharynx, trachea, & other passageways.
Transports cells & materials throughout the body. (Heart, blood vessels, blood, & lymph structures.)
Removes foreign chemicals & microorganisms from the bloodstream. (T-lymphocytes, B-lymphocytes, and macrophages; lymph structures.)
Removes metabolic wastes from the bloodstream. (Kidney, bladder, and associated ducts.)
Produces sex cells for the next generation. (Testes, ovaries, & associated reproductive structures.)
Sum of all chemical processes in the body. The sum total of all the chemical reactions occurring in body cells; the combined reactions of anabolism and catabolism.
The breakdown of organic matter, usually with the release of energy.
The buildup of organic matter, usually required an input of energy.
The result of contracting muscle cells. Movement can be voluntary, such as occurs in the muscles of the skeleton, or it can be involuntary, such as occurs in the muscle of the heart.
An increase in the size of body cells and/ or the body itself.
The ability of cells to receive stimuli and transport them from one body part to another. This characteristic is associated with nerve cells and muscle cells.
The ability of the body to replicate itself.
Production of sperm and egg cells and their union to form a fertilized egg cell, which develops into a new individual.
The duplication of a single cell. Asexual reproduction results in two identical daughter cells; asexual reproduction occurs in growth and repair.
The response of the body to internal and external stimulus.
The process of removing waste products from the body.
The steady state of equilibrium existing in the body and the body and the maintenance of this state.
Self regulating system that sends information back into the system to induce a response.
In the feedback system is the normal value of a variable factor such a temperature.
Receptor (or sensor)
Detects any deviation from set point in the feedback system.
Receives information in the feedback system from various receptors and integrates and determines the response needed to return to the set point.
Implement the response needed in the feedback system to return to normal homeostasis.
Negative feedback system
When the information decreases the systems output to bring the system back to it's set point.
Positive feedback system
Assist in maintaining homeostasis. In this situation, the information returned to the system increases the deviation from the set point.
Body is erect with eyes forward, feet together, arms at sides, and palms facing forward with the thumbs pointing away from the body.
Toward the front of the body on the belly side.
The belly side of a four legged creature, such as a dog.
Posterior or dorsal
Refers to the back side of the human body.
Toward the head or upward part of the body.
Cephalic and cranial
Are sometimes used instead of superior. Meaning towards the head or upward part of the body.
The direction away from the head or toward the lower part of the body.
Referring to the tail portion of a structure.